Hello, Developers. I'm using Marlin Firmware and Ramps 1.4(with arduino) I found very serious problem. When I plugged my extruder to the board, I can see "E" at arduino serial monitor and the system died. However, I can't find any code about the "E" in Marlin Firmware. Why the "E" is appeared? Here is copy of my Serial Monitor : start echo:Marlin1.0.0 echo: Last Updated: Apr 2 2016 17:46:by kaima7 - Developers